diff --git a/vendor/github.com/json-iterator/go/reflect_map.go b/vendor/github.com/json-iterator/go/reflect_map.go
new file mode 100644
index 0000000..547b442
--- /dev/null
+++ b/vendor/github.com/json-iterator/go/reflect_map.go
@@ -0,0 +1,338 @@
+package jsoniter
+
+import (
+	"fmt"
+	"github.com/modern-go/reflect2"
+	"io"
+	"reflect"
+	"sort"
+	"unsafe"
+)
+
+func decoderOfMap(ctx *ctx, typ reflect2.Type) ValDecoder {
+	mapType := typ.(*reflect2.UnsafeMapType)
+	keyDecoder := decoderOfMapKey(ctx.append("[mapKey]"), mapType.Key())
+	elemDecoder := decoderOfType(ctx.append("[mapElem]"), mapType.Elem())
+	return &mapDecoder{
+		mapType:     mapType,
+		keyType:     mapType.Key(),
+		elemType:    mapType.Elem(),
+		keyDecoder:  keyDecoder,
+		elemDecoder: elemDecoder,
+	}
+}
+
+func encoderOfMap(ctx *ctx, typ reflect2.Type) ValEncoder {
+	mapType := typ.(*reflect2.UnsafeMapType)
+	if ctx.sortMapKeys {
+		return &sortKeysMapEncoder{
+			mapType:     mapType,
+			keyEncoder:  encoderOfMapKey(ctx.append("[mapKey]"), mapType.Key()),
+			elemEncoder: encoderOfType(ctx.append("[mapElem]"), mapType.Elem()),
+		}
+	}
+	return &mapEncoder{
+		mapType:     mapType,
+		keyEncoder:  encoderOfMapKey(ctx.append("[mapKey]"), mapType.Key()),
+		elemEncoder: encoderOfType(ctx.append("[mapElem]"), mapType.Elem()),
+	}
+}
+
+func decoderOfMapKey(ctx *ctx, typ reflect2.Type) ValDecoder {
+	decoder := ctx.decoderExtension.CreateMapKeyDecoder(typ)
+	if decoder != nil {
+		return decoder
+	}
+	for _, extension := range ctx.extraExtensions {
+		decoder := extension.CreateMapKeyDecoder(typ)
+		if decoder != nil {
+			return decoder
+		}
+	}
+	switch typ.Kind() {
+	case reflect.String:
+		return decoderOfType(ctx, reflect2.DefaultTypeOfKind(reflect.String))
+	case reflect.Bool,
+		reflect.Uint8, reflect.Int8,
+		reflect.Uint16, reflect.Int16,
+		reflect.Uint32, reflect.Int32,
+		reflect.Uint64, reflect.Int64,
+		reflect.Uint, reflect.Int,
+		reflect.Float32, reflect.Float64,
+		reflect.Uintptr:
+		typ = reflect2.DefaultTypeOfKind(typ.Kind())
+		return &numericMapKeyDecoder{decoderOfType(ctx, typ)}
+	default:
+		ptrType := reflect2.PtrTo(typ)
+		if ptrType.Implements(unmarshalerType) {
+			return &referenceDecoder{
+				&unmarshalerDecoder{
+					valType: ptrType,
+				},
+			}
+		}
+		if typ.Implements(unmarshalerType) {
+			return &unmarshalerDecoder{
+				valType: typ,
+			}
+		}
+		if ptrType.Implements(textUnmarshalerType) {
+			return &referenceDecoder{
+				&textUnmarshalerDecoder{
+					valType: ptrType,
+				},
+			}
+		}
+		if typ.Implements(textUnmarshalerType) {
+			return &textUnmarshalerDecoder{
+				valType: typ,
+			}
+		}
+		return &lazyErrorDecoder{err: fmt.Errorf("unsupported map key type: %v", typ)}
+	}
+}
+
+func encoderOfMapKey(ctx *ctx, typ reflect2.Type) ValEncoder {
+	encoder := ctx.encoderExtension.CreateMapKeyEncoder(typ)
+	if encoder != nil {
+		return encoder
+	}
+	for _, extension := range ctx.extraExtensions {
+		encoder := extension.CreateMapKeyEncoder(typ)
+		if encoder != nil {
+			return encoder
+		}
+	}
+	switch typ.Kind() {
+	case reflect.String:
+		return encoderOfType(ctx, reflect2.DefaultTypeOfKind(reflect.String))
+	case reflect.Bool,
+		reflect.Uint8, reflect.Int8,
+		reflect.Uint16, reflect.Int16,
+		reflect.Uint32, reflect.Int32,
+		reflect.Uint64, reflect.Int64,
+		reflect.Uint, reflect.Int,
+		reflect.Float32, reflect.Float64,
+		reflect.Uintptr:
+		typ = reflect2.DefaultTypeOfKind(typ.Kind())
+		return &numericMapKeyEncoder{encoderOfType(ctx, typ)}
+	default:
+		if typ == textMarshalerType {
+			return &directTextMarshalerEncoder{
+				stringEncoder: ctx.EncoderOf(reflect2.TypeOf("")),
+			}
+		}
+		if typ.Implements(textMarshalerType) {
+			return &textMarshalerEncoder{
+				valType:       typ,
+				stringEncoder: ctx.EncoderOf(reflect2.TypeOf("")),
+			}
+		}
+		if typ.Kind() == reflect.Interface {
+			return &dynamicMapKeyEncoder{ctx, typ}
+		}
+		return &lazyErrorEncoder{err: fmt.Errorf("unsupported map key type: %v", typ)}
+	}
+}
+
+type mapDecoder struct {
+	mapType     *reflect2.UnsafeMapType
+	keyType     reflect2.Type
+	elemType    reflect2.Type
+	keyDecoder  ValDecoder
+	elemDecoder ValDecoder
+}
+
+func (decoder *mapDecoder) Decode(ptr unsafe.Pointer, iter *Iterator) {
+	mapType := decoder.mapType
+	c := iter.nextToken()
+	if c == 'n' {
+		iter.skipThreeBytes('u', 'l', 'l')
+		*(*unsafe.Pointer)(ptr) = nil
+		mapType.UnsafeSet(ptr, mapType.UnsafeNew())
+		return
+	}
+	if mapType.UnsafeIsNil(ptr) {
+		mapType.UnsafeSet(ptr, mapType.UnsafeMakeMap(0))
+	}
+	if c != '{' {
+		iter.ReportError("ReadMapCB", `expect { or n, but found `+string([]byte{c}))
+		return
+	}
+	c = iter.nextToken()
+	if c == '}' {
+		return
+	}
+	if c != '"' {
+		iter.ReportError("ReadMapCB", `expect " after }, but found `+string([]byte{c}))
+		return
+	}
+	iter.unreadByte()
+	key := decoder.keyType.UnsafeNew()
+	decoder.keyDecoder.Decode(key, iter)
+	c = iter.nextToken()
+	if c != ':' {
+		iter.ReportError("ReadMapCB", "expect : after object field, but found "+string([]byte{c}))
+		return
+	}
+	elem := decoder.elemType.UnsafeNew()
+	decoder.elemDecoder.Decode(elem, iter)
+	decoder.mapType.UnsafeSetIndex(ptr, key, elem)
+	for c = iter.nextToken(); c == ','; c = iter.nextToken() {
+		key := decoder.keyType.UnsafeNew()
+		decoder.keyDecoder.Decode(key, iter)
+		c = iter.nextToken()
+		if c != ':' {
+			iter.ReportError("ReadMapCB", "expect : after object field, but found "+string([]byte{c}))
+			return
+		}
+		elem := decoder.elemType.UnsafeNew()
+		decoder.elemDecoder.Decode(elem, iter)
+		decoder.mapType.UnsafeSetIndex(ptr, key, elem)
+	}
+	if c != '}' {
+		iter.ReportError("ReadMapCB", `expect }, but found `+string([]byte{c}))
+	}
+}
+
+type numericMapKeyDecoder struct {
+	decoder ValDecoder
+}
+
+func (decoder *numericMapKeyDecoder) Decode(ptr unsafe.Pointer, iter *Iterator) {
+	c := iter.nextToken()
+	if c != '"' {
+		iter.ReportError("ReadMapCB", `expect ", but found `+string([]byte{c}))
+		return
+	}
+	decoder.decoder.Decode(ptr, iter)
+	c = iter.nextToken()
+	if c != '"' {
+		iter.ReportError("ReadMapCB", `expect ", but found `+string([]byte{c}))
+		return
+	}
+}
+
+type numericMapKeyEncoder struct {
+	encoder ValEncoder
+}
+
+func (encoder *numericMapKeyEncoder) Encode(ptr unsafe.Pointer, stream *Stream) {
+	stream.writeByte('"')
+	encoder.encoder.Encode(ptr, stream)
+	stream.writeByte('"')
+}
+
+func (encoder *numericMapKeyEncoder) IsEmpty(ptr unsafe.Pointer) bool {
+	return false
+}
+
+type dynamicMapKeyEncoder struct {
+	ctx     *ctx
+	valType reflect2.Type
+}
+
+func (encoder *dynamicMapKeyEncoder) Encode(ptr unsafe.Pointer, stream *Stream) {
+	obj := encoder.valType.UnsafeIndirect(ptr)
+	encoderOfMapKey(encoder.ctx, reflect2.TypeOf(obj)).Encode(reflect2.PtrOf(obj), stream)
+}
+
+func (encoder *dynamicMapKeyEncoder) IsEmpty(ptr unsafe.Pointer) bool {
+	obj := encoder.valType.UnsafeIndirect(ptr)
+	return encoderOfMapKey(encoder.ctx, reflect2.TypeOf(obj)).IsEmpty(reflect2.PtrOf(obj))
+}
+
+type mapEncoder struct {
+	mapType     *reflect2.UnsafeMapType
+	keyEncoder  ValEncoder
+	elemEncoder ValEncoder
+}
+
+func (encoder *mapEncoder) Encode(ptr unsafe.Pointer, stream *Stream) {
+	stream.WriteObjectStart()
+	iter := encoder.mapType.UnsafeIterate(ptr)
+	for i := 0; iter.HasNext(); i++ {
+		if i != 0 {
+			stream.WriteMore()
+		}
+		key, elem := iter.UnsafeNext()
+		encoder.keyEncoder.Encode(key, stream)
+		if stream.indention > 0 {
+			stream.writeTwoBytes(byte(':'), byte(' '))
+		} else {
+			stream.writeByte(':')
+		}
+		encoder.elemEncoder.Encode(elem, stream)
+	}
+	stream.WriteObjectEnd()
+}
+
+func (encoder *mapEncoder) IsEmpty(ptr unsafe.Pointer) bool {
+	iter := encoder.mapType.UnsafeIterate(ptr)
+	return !iter.HasNext()
+}
+
+type sortKeysMapEncoder struct {
+	mapType     *reflect2.UnsafeMapType
+	keyEncoder  ValEncoder
+	elemEncoder ValEncoder
+}
+
+func (encoder *sortKeysMapEncoder) Encode(ptr unsafe.Pointer, stream *Stream) {
+	if *(*unsafe.Pointer)(ptr) == nil {
+		stream.WriteNil()
+		return
+	}
+	stream.WriteObjectStart()
+	mapIter := encoder.mapType.UnsafeIterate(ptr)
+	subStream := stream.cfg.BorrowStream(nil)
+	subIter := stream.cfg.BorrowIterator(nil)
+	keyValues := encodedKeyValues{}
+	for mapIter.HasNext() {
+		subStream.buf = make([]byte, 0, 64)
+		key, elem := mapIter.UnsafeNext()
+		encoder.keyEncoder.Encode(key, subStream)
+		if subStream.Error != nil && subStream.Error != io.EOF && stream.Error == nil {
+			stream.Error = subStream.Error
+		}
+		encodedKey := subStream.Buffer()
+		subIter.ResetBytes(encodedKey)
+		decodedKey := subIter.ReadString()
+		if stream.indention > 0 {
+			subStream.writeTwoBytes(byte(':'), byte(' '))
+		} else {
+			subStream.writeByte(':')
+		}
+		encoder.elemEncoder.Encode(elem, subStream)
+		keyValues = append(keyValues, encodedKV{
+			key:      decodedKey,
+			keyValue: subStream.Buffer(),
+		})
+	}
+	sort.Sort(keyValues)
+	for i, keyValue := range keyValues {
+		if i != 0 {
+			stream.WriteMore()
+		}
+		stream.Write(keyValue.keyValue)
+	}
+	stream.WriteObjectEnd()
+	stream.cfg.ReturnStream(subStream)
+	stream.cfg.ReturnIterator(subIter)
+}
+
+func (encoder *sortKeysMapEncoder) IsEmpty(ptr unsafe.Pointer) bool {
+	iter := encoder.mapType.UnsafeIterate(ptr)
+	return !iter.HasNext()
+}
+
+type encodedKeyValues []encodedKV
+
+type encodedKV struct {
+	key      string
+	keyValue []byte
+}
+
+func (sv encodedKeyValues) Len() int           { return len(sv) }
+func (sv encodedKeyValues) Swap(i, j int)      { sv[i], sv[j] = sv[j], sv[i] }
+func (sv encodedKeyValues) Less(i, j int) bool { return sv[i].key < sv[j].key }